Sewing machine clamps



July 1, 1958 H. E. ALTHENs v2,841,106

SEWING MACHINE cLAMPs Filed May 9, 1955 AGE T United States Patent O wReece Corporation, Waltham, Mass., a corporation of MassachusettsApplication May 9, 1955, Serial No. 506,907 Claims. (Cl. 112-237) Thisinvention relates to a sewing machine and more particularly to means forraising and lowering a button holding presser foot of a button sewingmachine.

In sewing machines for attaching buttons to a garment the garment isusually held by a work clamp which moves laterally in a horizontal planeso as to locate the garment and the button to be attached thereto in aposition whereby a needle which reciprocates in a stationary Verticalpath will pass through the holes of the button alternately. Theamplitude of the lateral movement of the work clamp must also beadjustable to accommodate buttons having various spacings between theirholes. The work clamp is usually provided with a lower member whichengages the underside of the work andan upper presser foot member whichpresses down on the top of the work to hold it in position on the lowermember. The upper member is usually in the for-m of a clamp whichreceives the button and holds it in place for sewing.

In this invention the upper presser foot member is mounted on a rod forvertical movement in a sleeve which is fixedly mounted on an upperextension of the lower portion of the clamp. Connections are providedbetween the rod and a treadle for raising and lowering the clamp. If theconnecting means are attached to only one side of the rod, there will bea tendency for the rod to tilt in the sleeve and cause the rod to bindtherein. If the means are connected to both sides of the rod thepressure on both sides must be equal or a similar binding will occur.

Since the position of the treadle and part of the connecting means willremain xed while the work clamp shifts the binding tendency of the rodin the sleeve will be increased when the clamp is shifted into its mostextreme positions. In the case of the connecting means being connectedto opposite sides of the rod one connection will be longer than theother and it will be necessary to provide a means for equalizing thelengths of the connecting means. It is therefore an object of thisinvention to provide means for actuating the button holding presser footwhich will exert an equal pressure on both sides of the presser footmounting rod when it is being actuated.

Another object of this invention is to provide a novel means for raisingand lowering a. button holding presser foot of a button sewing machine.

A further object of this invention is to provide a novel means forequalizing the tension on cables attached to opposite sides of a rodwhich is slidable in a sleeve so that the rod will not bind in thesleeve when actuated by the cables.

Still another object of this invention is to provide means whereby thetension exerted on opposite sides of a presser foot for raising the samewill be equal regardless of the position of the work clamp.

Yet another object of the present invention is to provide means forequalizing the tension on cables having slightly different lengths andwhich are connected at one of their ends to a rod slidable in a sleeveand at their l 2,841,106 Patented July 1, 1958 ACC 2 other end to thesame actuating member whereby bind# ing of the rod in the sleeve will beeliminated when the rod moves therein under the influence of the cablesand the actuating member.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

Figure 1 is a vertical elevation of the right side of the machine withparts broken away;

Figure 2 is a cross section view taken on line 2 2 of Figure l; and,

Figure 3 is a vertical sectional view taken on line 3 3 of Figure 1.

Referring now more particularly to the accompanying drawings there isillustrated in Figure 1, a sewing machine for attaching buttons to agarment which comprises a bed plate 1t), an upwardly extending portion12 at the rear of the bed plate 10 and an overhanging arm 14 whichextends forwardly from the vertical portion 12 above the bed plate 16.The bed plate 10 contains the looper mechanism, not sho-wn, and theoverhanging arm carries the needle bar actuating mechanism also notshown.

The overhanging arm 14 is provided with a central downwardly extendingU-shaped portion 16 the legs of which are provided with axially alignedopenings 18 and 20. The opening 18 is larger than the opening 20 and hasmounted therein a bushing 22 which is provided with a central opening 24therethrough having the same diameter as the opening 2t). A shaft 26extends through the openings 20 and 24 and has a portion thereofextending forwardly of the U-shaped portion 16. The shaft 26 is mountedso as to be freely movable longitudinally in the openings 20 and 24 aswell as being rotatable therein about its axis.

A U-shaped member 28 is disposed within the opening formed by the bedplate 10, the vertical portion 12 and the overhanging arm 14. The member28 is open at the front and is provided with a boss 30 which receivesthe `forward portion of the shaft 26. The boss 30 is provided with aslit 32 and has screws 34 mounted thereon for tightening the boss 34 onthe shaft 26 for preventing relative movement therebetween. Secured toor integral with the forward upper end of the member 28 is a sleeve 36having a vertically extending bore 38 therein. A hollow rod 40 which hasa spring 42 disposed therein is mounted in the sleeve 36 for verticalmovement, see Figures 2 and 3. Secured to the lower end of the rod i0 isa button holding presser foot indicated generally at 44. The presserfoot 44 coacts with the forward lower end of the member 28 to clamp thework in position.

The spring 42 is of a length so that it extends above the upper end ofthe rod 40 and the sleeve 36 is provided with a plate 46 which closesthe upper end of the bore 33. Suitable screws 48 hold the plate 46 inposition and the .spring 42 bears against the plate 46 to urge thepresser foot 44 downwardly to clamp the work. The lower end of thesleeve 36 is'cut away as at 50 and a plate S2 is held in the cut awayportion by screws 54. The rod 40 is provided with a slabbed portion 56which bears against the plate 52 to prevent rotation of the rod 40 inthe sleeve 36.

Fixedly secured to the shaft 26 intermediate the legs of portion 16 is acollar 58 having an arm, not shown, which is connected to a mechanismfor oscillating the shaft 26 about its longitudinal axis. The collar 58is provided witha Vslotitlwhich receives a pin 62 mounted on an arm 64.The arm1`64 is connected to a mechanism,

not shown, for moving the shaft lengthwise of its longitudinal axis.Thus it will be seen that the lower end of the member 28 can be movedfrom one side to the other so that the needle may pass alternatelythrough the holes in a button held in the presser foot and may beshifted forwardly and rearwardly when sewing a four hole buttOIl.

The rod 40 is provided with a projection 66 extending from each sidethereof to which are secured the ends of two cables 68 one of which isshown in Figure 1. The other end of each of these cables is secured tothe end of one of a pair of levers 70, one of which is shown in Figure1, and which are fixedly mounted on a cross shaft 72. Fixedly mounted onthe shaft 72 is a lever 74 which carries at its upper end a pin 76 whichis engaged by the forked end 78 of a lever 80 xed on a rock shaft 82.

Mounted on the rock shaft 82 is a lever 84 which has secured to its freeend a cable or chain 86. The other end of the cable or chain 86 isconnected to a foot pedal, not shown, by which the button clamp may beraised or lowered.

The cables 68 pass over sheaves 92 carried on the ends of a shaft 94mounted in a bore 96 in the upper arm of member 28. The shaft 94 isenlarged in the middle and tapered slightly toward the ends as shown inFigure 2, whereby the shaft 94 can rock or tilt within the bore 96. Alsomounted on the shaft 94 outwardly of each of the sheaves 92 is a guard98 to retain the cables 68 in position on the sheaves 92.

It will thus be seen that by providing a tilting or rocking movement ofthe shaft 94 the position of the sheaves 92 will be automaticallyadjusted when the cables 68 are 'tensioned so that the pull on theopposite sides of the rod 40 will be equal. This will automaticallycompensate for slight variations in the lengths of the cables. Furthersince the clamp must be adjustable for various size buttons the use ofshaft 94 will compensate for Variations in the distance between the endsof levers 70 and the projections 66 caused by the differences betweenthe center line of the machine and the points of attachment of thecables 68 to the rod 40 when the machine is adjusted to provide more orless sidewise movement of the work clamp. t

' From the foregoing, the construction and operation of the device willbe readily understood and further explanation is believed to beunnecessary. However, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction shown and described, andaccordingly all 'suitable modifications and equivalents may be resortedto, falling within the scope of the appended claims.

I claim:

1. In a sewing machine, a work clamp, said work clamp including a lowerwork supporting member and a presser foot member coacting therewith forclamping work therebetween, a single post mounted on said work clamp forvertical movement thereon with respect to said lowerwork supportingmember, said presser foot being mounted on said post for movementtherewith, actuating means for raising and lowering said presser footmember with respect to said Work supporting member, said actuating meansincluding a pair of cables connected to opposite sides of said post, andmeans for equalizing the pressure exerted on the opposite sides of thepost by the actuating means when said presser foot is being raised.

2. The combination of claim 1 wherein said actuating means includes aplurality of interconnected links mounted for pivotal movement on saidmachine, one of said links being connected to a foot pedal, others ofsaid links being connected by said cables to the opposite sides of saidpost whereby actuation of said foot pedal will move said presser footmember.

3. The combination of claim 2 wherein said equalizing means includes apair of sheaves over which said cables pass, said `sheaves being mountedon `opposite ends of a shaft, and means permitting said shaft to rockabout a point intermediate its length.

4. The combination of claim 3 wherein said work clamp includes an upperarm spaced above and overlying said work supporting member, a transversebore having a constant diameter in said upper arm, said shaft beingenlarged at its middle and being tapered towards its opposite ends, saidshaft being mounted in said bore whereby it may rock on its enlargedportion.

5. An equalizing means for equalizing the tension on a pair of cableshaving one of their ends connected on opposite sides of a member to bemoved and their other ends connected to an actuating member, said meansincluding a pair of sheaves over which said cables pass, said sheavesbeing mounted on opposite ends of a shaft, and means permitting saidshaft to rock about a point intermediate its ends, said last named meansincluding an enlarged portion at the center of said shaft, said shaftbeing tapered towards its opposite ends, and a bore having a constantdiameter in which said shaft is mounted.

References Cited in the file of this patent UNITED STATES PATENTS1,119,100 Mills Dec. l, 1914 1,620,249 Corrall et al Mar. 8, 19271,841,958 Kendall et al. Jan. 19, 1932 2,327,021 Cushman Aug. 17, 19432,510,014 Faulkner May 30, 1950

